greene



(No Model.) 3 Sheets-Sheet 1. D. AGREENE.

DRIER.

No. 337,948. Patented Mar. 16, 1886.

(No Model.) 3 SheetsS heet 2. D. A. GREENE.

DRIER.

No. 337,948. Patented Mar. 16, 1886.

N. PETERS. Photwulho n lmr. Washington. 0.0.

(No Model.) 3 Sheets-Sheet 3. D. A. GREENE. DRIER. No. 337,948.

Patented Mar. 16, 1886.

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E arr ,B y hi3 092%? UNITED STATES PATENT @rrrcn.

DARWVIN A. GREENE, OF NEW YORK, N. Y.

DRIER.

SPECIFICATION forming part of Letters Patent No. 337,948, dated March 16, 1886.

Application filed October 16, 1885. Serial No.180,067. (No model.)

To aZZ whom it may concern.-

Be it known that I, DARWIN A. GREENE, of New York city, in the county and State of New York, have invented certain new and usefulImprovementsinDrying-KilnsAdapted for Treating Kindling-Wood; and I do hereby declare that the following is a full and exact description thereof.

I effect the drying with steam heat, which raises the temperature of a great volume of dry-air which is drawn through the mass of wood while the latter is moving slowly downward in a deep bin.

In the localities where my apparatus will be employed fuel is plenty and cheap, the waste or unmerchantable wood being usually sufficient to produce more steam than is required for effecting the drying; but there are difficulties which have heretofore seriously interfered with the success of such apparatus. My invention is intended to surmount these difficulties.

1 provide an apparatus of great capacity at small cost, and effectually guard against encumbering or clogging the steam -heating pipes by any contact of the wood or of any dust or dirt therefrom. The air is caused to move in contact with the heating-pipes and become raised in temperature, and thence to be movedthrough the interstices in the large mass of wood while under asuction or partial vacuum, so that the openings through which the wood is drawn out and any openings or leaks in the apparatus will draw inward instead of forcing out air. The apparatus should be of such depth that the wood is twenty-four or more hours in moving downward through it. At the top the wood is thrown in by an elevator, or otherwise, cold, and under conditions often occurring in practice, soaked, saturated with water. A current of hot air rising from the wood below thoroughly warms this fuel during the first few hours. As it descends lower by the removal of the dried wood at the bottom it finds a gradually changing, hygrometric condition, the air near the bottom being hot and dry. I provide such conditions that the entire interior of the kiln is under a partial vacuum. This materially contributes to the successful working.

The accompanying drawings form a part of this specification, and represent what I consider the best means of carrying out the invention.

Figure 1 is ageneral vertical section through the entire apparatus. Fig. 2 is a section through a portion on the linewx in Fig. 1. Fig. 3 is a horizontal section on the line y y in Fig. 1. Fig.4. is an elevation, partly in section, showing my kiln, seen at right angles to the view in Fig. 1. The left side is an elevation. The right side is a central vertical section. The lower portion of the middle is a section on the line 2 z in Fig.1. Fig. 5 is a plan of the gallery-head at the top of the kiln, showing the chutes into the body. Some of the details are slightly different in these figures, but not so as to introduce any confusion. Either construction of the parts may be adopted, as may be preferred. The remaining figures show a considerable modification. Fig. 6 is an end elevation, partlyin section, of a straight'sided or square kiln, with the bottom shutter extending in one direction across the full width of the kiln. It has substantially similar heater-coils, air-fines, exhaustfans, dampers in the wind-boxes, andsprocketwheels for carriers. It has also sprocketwheels for a horizontal conveyer below the kiln-bottom. Fig. 7 is aside elevation, partly in section. being a view at right angles to the View in Fig. 6.

Similar letters of reference indicate corresponding parts in all the figures where they occur. 1

Referring to Figs. 1 to 5, inclusive, A is the main building, and B certain open-work partitions therein,provided with inclined slats b, which perform the important functions of al lowing heated air to flow in freely and move upward through the interstices in the mass of wood without letting any chips or dirt escape through these portions of theapparatus. The bin or chamber in which the wood is contained is high. It receives the wood at the top, either constantly or at short intervals. The dried wood to be bundled is taken away from the bottom and the mass gradually settles, being dried on its passage by a liberal flow of warm air, which enters through the slats and rises through the mass.

D D D are sets of pipes filled with live steam, technically known as coils. They may be in the form of coils or helices, or they may be in straight lengths variously connected. In any arrangement live steam is admitted at a good pressure from a steam boiler or boilers (not represented) entering through pipes 0, controlled by valves 0. tedfreely from the external atmosphere to circulate through these coils, being heated thereby. The air thus warmed is delivered through the partitions B into the mass of wood near the bottom. The slats b, by their inclined positions, retain the wood within the bin or chamber M and compel it to descend in the converging space. At the extreme bottom on each side are sufficient apertures 6, through which the dried wood is taken out by hand or by machinery and bundled.

G is an upright flue with a suitable hood, to exclude the weather, connecting with the top of the bin or chamber M. Y

H is a valve controlled by means of a rod connecting with an arm, H. This valve is above the'point of connection of the flue with the bin. I is another valve similarly controlled. (See Fig. 5.) This valve is below the point of connection of the flue with the bin.

J is apassagedescending from the flueGand communicating with efficient exhansters K, impelled by a steam-engine or other suitable means,(not represented,) which exert a strong exhausting force, drawing the airdown through the passage .J.

When it is desired simply to use the natural draft due to the levity of the warm air, the exhausters K are stopped, the valve I closed, and the valve H opened. Under these conditions the hot air from the coils enters the mass of wood through the slatted partitions B, and, rising through the interstices in the wood, escapes loaded with moisture, but still with a sufficiently high temperature to maintain adraft. Thus conditioned it emerges from the top of the bin into the flue G-and rises upward past the open valve H and is discharged through the hooded top. There are some conditions of wood and of weather under which this draft is not sufficient. Then the exhaust ers K are started, the valve I opened, and the valve H closed. Under these conditions the air is drawn more forcibly than by the natural draft. The fact that it is compelled to descend is of little importance in view of the strong positive force exercised by the exhausters. This agency induces a partial vacuum in the descending passage J. To supply this, the air is drawn with much force through the entire round of movements, first circulating through the steam-coils and becoming heated, and then moving inward through the slatted partitions B b; thence upward through the mass of wood in the bin; thence downward through the passage J, and out through the liberal apertures in which the exhausters K are placed. It will now be seen thata partial vacuum obtains in the lower portion of the bin M, whether the apparatus is being worked Cold air is admit.-.

by the natural draft or by the exhausters. The apertures between the inclined slats b put in the warm air at points somewhat'above the bottom. The extreme-bottom of the bin receives cold air, which enters through the apertures e at which the wood is being drawn out. The coldair entering in this manner cools the wood and becomes itself warmed. It mingles. with the hotter air received through the slatted openings, and contributes somewhat .to the drying influence. The cooling effect on the wood immediately before the latter is delivered is of advantage in preparing the wood to be bundled and stored in the best condition. i

I provide efficiently against accidental fires from any cause. L L are valves controlled by valve-stems L, leading to the exterior of the building. These valves on being opened discharge the live steam at full'pressure in immense volumes into the bin, ordinary means as doors, (not represented)being provided to exclude the air from the coils. These devices provide efficient nieansfor filling all the interstices in the bin with steam instead of air.

The large quantity of kindling-Wood well dried, in the lower portion, with a strong draft inward from other portions of the apparatus, may be peculiaril'y susceptible tofire. The provision for excluding air and filling the bin with steam may be very i1nportant,either in extinguishing the fire altogether or in holding it in check until water can be applied in sufficient quantities. a

The wood may be introduced through the aperture min the top of the bin by hand, or by any suitable machinery. I have not considered it necessary to represent fully any mechanism for this purpose.

P P, Fig. 4, indicate sprocket-wheels, which may be connectedwith chains and pushers manner to bring up the wood from sawing and splitting machines, which may be at any desired lower level. There may-be any number of elevators and any number of horizontal carriers to supply the wood. There may be any number of such devices to aid in taking away the Wood and supplying it to bundling-niachines.

My invention does not depend on any particular mode of supplying the wood or of bundling and carrying it away. p I

Although I have so far referred to only one line, G, and correspondingly to only one of various other parts, it will be seen, by referring to Fig. 4, that there are two of theflues G, each equipped with its controlling-valves erable number of the apertures 12, through which the wood is taken out to be bundled and through which cold air is admitted. I attach importance to this arrangement as allowing a considerable diversity of the rate of supply at the different apertures m or a considerable diversity in the rate of withdrawal through the different apertures e, or both, without interfering with the practically uniform operation of the apparatus.

Certain parts may be entirely thrown out of use for a period. For example, I can, in case of leakage or other failure of one of the steamcoils, shut off the steam therefrom and allow it to become cold, and proceed to repair it while the other portions of the apparatus continue to work efficiently. In such case it will be obvious that those discharge-apertures e which are nearest to the unused heating-coil should be thrown out of use. Obviously in such cases the unused apertures 6 should be closed. Such may be effected by a slide (not represented) or by any ordinary deviceas a flexible blanket applied on the exterior ofeach orificeso as to prevent the induction of air through those unused parts of the apparatus.

It will also be seen from this figure that the inclined partitions B, arranged like an inverted V in the center of the structure, do not extend the entire length of thebin, but terminate near each end with correspondingly-inclined ends, and that these ends are also correspondinglyslatted. Theentirearrangement allows the kindling-wood to descend in a mass, filling the whole structure uniformly until it reaches the top of this inverted V. Below this it is divided. The inclined positions of the central partitions and the reversely-inclined positions of the outer partitions cause the wood to descend smoothly and to be led directly to the apertures e. I attach importance to this arrangement, as providing no dead-space in which wood may accumulate and remain.

In the modification shown in Figs. 6 and 7, the bin is of uniform width through the principal portion of its height. The slatted partitions 13 b are of less area and are inclined so as to deliver the wood through a single aperture. The action is the same. The wood delivered in the top wet and cold is warmed by the current of hot damp air rising through the interstices in the wood below. Asit gradually descends it parts with its moisture, and in the lower halt of the bin is subjected to eminently desiccating conditions. In the extreme lower portion of its traverse in the bin it is rapidly cooled by meeting a stream of cold air. It is delivered dry, with the exterior cooled, the best attainable conditions for compression in bundles by suitable machinery, tying or wirin g, and delivery for storage or transportation.

Further modifications may be made in various parts of the structure without departing from the principle or sacrificing the advan tages of the invention.

I can use a much greater number of the steam-heating coils.

Any suitable form of apparatus may be provided for taking away the condensed water and returning it to the boiler.

I propose in some cases to establish fixed perpendicularpartitions, dividing thebin into three relatively independent bins, each of which shall receive wood through a suitable opening, m, in the top,'and deliver it through a number of openings, B, at the bottom. In such case when a portion of the apparatus is thrown out of use the introduction of wood through the corresponding top aperture, m, should be stopped, which may be done by closing the aperture with a suitable slide. This modification will be understood without a separate drawing. It would be fully carried out by simply introducing partitions in Fig. 2 at the points where the joists are shown extending up and down, so as to divide the bin into three equal parts.

I can use exhaust-steam instead of live steam in the several coils. In such case I provide a separate pipe bringing live steam to the valves L to aid in suppressing and extinguishing fires.

Although I have shown only three kilns, or three sets of heating-coils and three places to introduce wood, it will be understood that the structure may be prolonged indefinitely.

This invention is intended more particularly for utilizing the waste of saw-mills.

At a' large lumber center any number of kilns may be placed side by side and worked in connection.

The end inclines may be omitted in any case, and the double inclines, which form the central portion of the'apparatus, may be extended quite to the ends. This arrangement allows access through a door at one end or both ends for repairs; but for ordinary cases I prefer the form shown. Access for repairs may easily be obtained through the floor.

Under many conditions sufficient heat will be deflected by the series of coils D in the center alone. In such case all the air will be admitted through that coil and through the adjacent slatted partitions. The access of air through the coils D D and through the slatted partitions adjacent thereto should be shut off.

One important end attained by my arrangement of the lines is that the exhausters and other machinery which are heavy are down near the lower fioor.

Under ordinary conditions the apparatus will be worked with the exhausters during the entire daytime while the wood is descending actively, and at night live steam will be let into or continued in the several coils, and the exhausters will be stopped, and the valves H I adjusted to allow natural draft. The kiln will thus conditioned work by natural draft by night.

The modification shown in Figs. 6 and 7 is more particularly adapted for treating wood which is to be delivered loose in bulk.

I make the kiln without any floor, leaving the air free to rise between the floor-timbers,

thus obtaining the most liberal space for its access.

In case of fire the steam can readily expel the air by simply closing both sets of valves H and I. Ihe live steam will rapidly fill the entire bin and flow out through the bottom.

I claim as my invention- 1. In a kiln for drying kindling-wood, abin having eXhauster K, for taking away air and vapors from the top and maintaining a partial vacuum in the interior, in combination with one or more gratings, as B, an inlet for admitting fresh dry air thereto from the external atmosphere, and heaters, as D D D for heating such air before its admission through the grates, all combined and arranged forjoint operation, substantially as and for the purposes herein specified.

2. The two valves arranged one above and one below each bin-exit, in combination with the drying-bin M, having inlets for introducing drying-air and draft-exits at the top of flues, as G, connecting with such exits, exhaust-fines, as J, and means, as K, for mechanically creating a vacuum therein, and having 25 connections with said exit-apertures, whereby the natural draft or the exhaust mechanism may be applied at will, as set forth.

3. In a kiln for drying kindling-wood, the" bin M, in which the wood is slowly descending during the drying operation, in combination with exhauster K, for taking away the air and vapor from the top and maintaining a partial vacuum in the interior, and with a,

DARWIN GREENE.

Witnesses:

M. F. BOYLE, MAMERRE ELLISON. 

